This invention relates to portable cribs and playpens for infant use and particularly to those portable cribs and playpens comprising fabric structure by which a child is supported and confined.
The prior art for cribs and playpens which are portable or at least foldable, is extensive. Many of these cribs or playpens achieve portability or foldability by means of fabric structures. For example, U.S. Pat. No. 2,537,903 issued to Markowitz discloses a highly portable fabric crib structure in which the crib comprises opposing fabric pockets defining crib ends which are adapted to fit over the backs of facing chairs and thereby support crib side panels extending between the crib end pockets by means of tension applied by the chair backs. However well suited this embodiment is with respect to portability, it is not a safe crib structure. In particular, it would be hazardous to a child who is able to stand up in the crib since as a child attempts to stand and support himself on the fabric side elements, the fabric side panels will readily flex outward. This flexing of fabric side panels would cause the center of gravity of the crib and child to shift and in some cases cause the center of gravity to shift so much that the crib would tip. Clearly, the flexibility of fabric structures can be a major obstacle to designing a safe fabric crib or fabric playpen.
A significant improvement in safety over the Markowitz patent is represented by U.S. Pat. No. 4,538,309 issued to Gunter. That patent discloses a portable playpen with a disassembable frame and a one-piece fabric body made from adjoining rectangular panels, the fabric body suspended from the frame at upright corner posts. The rigidity or flexibility of the side panels and floor are therefore determined by the amount of tension applied to them by the suspending corner posts. The amount of rigidity that can be built into this crib design is therefore limited by the strength of the fabric and seams and even more limited by the strength of the person who will be assembling it.
Unfortunately, a crib design following even the improved teachings of the Gunter patent and which can be readily assembled proves too flexible in the floor and the sides. The weight of the child alone causes the floor to flex into a substantial arc and a child placing his weight and energy onto the side panels will cause them to flex a considerable amount. While this flexing of the floor and side panels may not pose a hazard to the child, it does not make the crib or playpen comfortable for a child to stand in or move about in.
It is therefore an object of the present invention to provide a playpen or crib having a fabric design with all of the known advantages of the best fabric designs such as safety, machine washability, light weight and portability, and easy assembly and disassembly, but which also has the advantages of side and floor rigidity and strength which are more commonly associated with cribs and playpens designed from rigid materials.